Method and apparatus for using channel output feedback in multi user wireless systems and hybrid-arq

A method for transmitting a signal using a channel output feedback in a terminal, the method comprising:

• receiving information for a precoder from the base station;
• transmitting a first packet on the received precoder to the base station;
• receiving a Channel Output Feedback (COF) of the transmitted first packet from the base station;
• receiving information for transmitting a second packet from the base station, wherein the information for transmitting the second packet is determined based on a channel output of the transmitted first packet;
• preparing a variant of the second packet using the COF and the received information for transmitting the second packet;
• and
• transmitting the prepared variant to the base station.

A base station for receiving a signal using a channel output feedback, the base station comprising:

• a transmitter configured to transmit, to a terminal, information for a precoder;
• a receiver configured to receive, from the terminal, a first packet on the transmitted precoder;
• and
• a controller configured to control to feed back a channel output of the received first packet, to determine information for transmitting a second packet based on the channel output, to control to transmit the determined information for transmitting a second packet to the terminal, and to control to receive a second packet from the terminal, wherein the second packet is a variant of an original signal prepared using the COF and the transmitted information for transmitting the second packet.

A method for receiving a signal using a channel output feedback in a base station, the method comprising:

• transmitting information for a precoder to a terminal;
• receiving a first packet on the transmitted precoder from the terminal;
• feeding back a channel output of the received first packet to the terminal;
• determining information for transmitting a second packet based on the channel output;
• transmitting the determined information for transmitting a second packet to the terminal;
• and
• receiving a second packet from the terminal, wherein the second packet is a variant of an original signal prepared using the COF and the transmitted information for transmitting the second packet.